Determination of the naturally occurring vanadium-complex amavadin in Amanita muscaria with HPLC-ICPMS

The determination of the two isomers of amavadin and other V species in Amanita muscaria with HPLC-ICPMS.


Chemicals and instruments
Ultrapure water (18.2 MΩ*cm) was used throughout the study.
The certified reference materials (CRMs) SRM 1573a (Tomato Leaves) and SRM 1640a (Trace Elements in Natural Water) were obtained from the National Institute of Standards and Technology (NIST, Gaithersburg, USA).
Air-and moisture sensitive reactions were carried out following standard Schlenk technique with Ar as inert atmosphere. NMR spectra were measured on a Bruker (Rheinstetten, Germany) Advance III 300 MHz NMR spectrometer in deuterated solvents. 1 H NMR spectra were recorded at 300.13 MHz and 13 C NMR at 75.48 MHz and were referenced to the respective solvent peak. The chemical shifts δ are given in ppm. The multiplicity of peaks is denoted as singlet (s), doublet (d), triplet (t), quadruplet (q), and multiplet (m). All samples were prepared in air in standard 5 mm NMR tubes.
Samples were measured in air in the solid state at 24 scans and 4 cm -1 resolution in a spectral range of 400-4000 cm -1 .
Total V concentrations were determined on a 7700x ICPMS (Agilent Technologies).
For speciation analysis, a 1260 Infinity HPLC (Agilent Technologies) was coupled to a 7700x ICPMS or a tandem ICPMS (ICPMS/MS, 8900, Agilent Technologies). A silica-based strong anion-exchange column (Zorbax SAX, 4.6 * 150 mm, 5 µm, Agilent Technologies) was used for separation of the V species. The outlet of the column was connected to the nebulizer of the ICPMS via polyether ether ketone (PEEK) tubing, with an inner diameter of 0.125 mm.
The water content of the mushroom samples was determined with a SMART Trac II Moisture & Fat Analyzer (CEM, Kamp-Lintfort, Germany). An ulraClave IV (MLS GmbH, Leutkirch, Germany) was used for microwave assisted digestions. Synthesis intermediates and extracts were centrifuged at 3300*g on a Rotina 420 R (Hettich Lab Technology, Tuttlingen, Germany).